Answer:
your answer is C.both A and B
Answer:
A) micro defects are left behind on the surface of metal components during the manufacturing process. These defects, in the form of micro-cracks or pits, becomes initiation sites for crack propagation or corrosion. Removing these imperfections on the surface of metal parts by electroplating greatly improves the life of metal components.
B) it will reduce fatigue crack growth.
Dispersion hardening involves the inclusion of small, hard particles in the metal, thus restricting the movement of dislocations, and thereby raising the strength properties. In dispersion hardening it is assumed that the precipitates do not deform with the matrix and that a moving dislocation bypasses the obstacles (precipitates) by moving in the clean pieces of crystal between the precipitated particles.
C) stress concentrations such as changes in section with sharp corners caused yielding, which will typically occur first at a stress concentration. For ductile materials localised plastic deformation can cause a redistribution of stress, enabling the component to continue to carry load. Brittle materials will typically fail at the stress concentration. Repeated loading may cause a fatigue crack to initiate and slowly grow at a stress concentration leading to the failure of even ductile materials. Fatigue cracks always start at stress raisers, so removing such defects increases the fatigue strength.
The following appliance parts gets the hardest services is a line cord.
The answer is D.
(U didn’t write the right.)
Answer:
Plastic deformation, irreversible or permanent. Deformation mode in which the material does not return to its original shape after removing the applied load. This happens because, in plastic deformation, the material undergoes irreversible thermodynamic changes by acquiring greater elastic potential energy.
Elastic deformation, reversible or non-permanent. the body regains its original shape by removing the force that causes the deformation. In this type of deformation, the solid, by varying its tension state and increasing its internal energy in the form of elastic potential energy, only goes through reversible thermodynamic changes.
